Why should a game include a range of possible damage values per hit?

Question

I’m asking this because this reminds me of critical hits, preventing battles from being too predictable, BUT if I already have crits… why would I have damage ranges?

Especially in action games, there’s so much going on that you don’t get to notice the bigger hits (unlike turn-based games, where you can nearly feel them), so the question is…

Why would I keep damage ranges in my ARPG? What are the basic considerations? Are there common patterns like “always limit it to 10%” or “make it 30 if such and such…”?

In this game I’m talking about, it may be relevant to know you cannot dodge hits, so everything is RNG, from the odds of being hit to the amount of damage you take.

Answer 1

One thing that randomness of damage does is to make it so that the benefit of additional health behaves more linearly.

Consider the case where an attack always does 100 damage. In that case a health value anywhere between 101 and 200 has the same effect - it takes two hits to reduce that to zero. With some damage randomness, it's no longer the case that having 101 health is twice as good as having 100 health.

Obviously that example is fairly extreme, and those effects are reduced when the damage is small relative to the quantity of health, and where you have a variety of different attacks.

Answer 2

This all comes down to your goals for your game. You need to ask yourself: "why am I considering adding variable damage? What problem does it help fix, or what player experience does it help serve?"

As you note, randomized damage provides roughly the types of gameplay impacts we get from critical hits, so most of the reasons discussed in that Q&A thread can also apply to non-critical damage variation, if you find your critical hits alone aren't fully serving those goals.

A reason to pursue randomized damage ranges beyond just discrete criticals could be verisimilitude: the real world is messy. Even an expert in a skill usually doesn't perform it identically every time. So an element of randomness in the exact damage number can express that, and make the character's actions feel slightly more organically inconsistent, rather than mechanically same-y.

But if your game is about robots or computer programs battling in the digital world, maybe that kind of organicity actually speaks against your game's thematic goals.

One reason to not have randomized damage is if you want to make it easy for the player to predict the outcome several steps into the future, like a tactics game, or one with RPG elements where you want the player to be able to make analytical judgements about which build to use. And where you want this type of min-maxing gameplay to be clearly legible and learnable, not obfuscated behind a layer of superficial variation.

But if you're designing a game for more casual play and don't want players getting sucked into analysis paralysis where they try to min-max every encounter, a little random fuzz can help them resist that temptation.

The more random variation you add, the more inconsistent the gameplay can feel. On the plus side, this can keep the player on their toes, or force them to mix up their play when the random rolls don't always come out the same, increasing variety and combatting stagnant dominant strategies. But too much can make the game feel capricious, like it's "cheating", or de-value player agency, and also make your mechanics harder to learn (especially if you have small percent damage buffs whose effects can get swamped by random noise).

So you need to interrogate what you want out of your game's combat system, what you're getting out of your existing critical mechanics, and whether there's a delta left over that needs to be served by additional variation or other changes to your systems.

Answer 3

Some baseline effects to consider

Slow games
If your game has only few instances of damage happening at a time (for example turn based games), having damage variation adds unpredicatability beyond the binary of crit vs non-crit. With just crit or non-crit you can find yourself for example in a situation where you "need" at least one crit in your next three attacks to win the encounter with a certain strategy. That is easy to math out and appeals to an audience that likes to plan ahead with a very good sense of probabilites and then see if their plan is supported by their luck or not. Damage variation to a reasonable degree can quickly make the needed calculations for "how many hits do I need?" almost unmanageable, appealing more to a audence that plans less and just makes decisions on the get go for the next move based on the current situation. On a sitenote, having damage variation that is more influential than crits can leave a bad taste. Example: you deal 1-6 damage and have a 10% chance to crit for 2x damage. Then you can have "crits" deal only 2 damage (often accompanied by some extra oomph animation) while a normal hit might deal 6 damage (without that animation), leading to the feeling of a "wasted" crit. Therefore I'd suggest either keeping the damage variation below the "crit-multiplier" or having other mechanics preventing that kind of experience.

Fast games
In fast games with LOTS of hits damage variation evens out really quick and is often not very interesting as a game mechanic. In contrast to critical hits which often have a possibility to "invest" into as a mean to increase your damage output, most games do not feature such an opportunity into "damage variation".
However there are games that do allow investment into that factor. For example Path of Exile, where for some builds only the hardest hit in the last few seconds is important, so they invest into an item that increases the damage variation to higher highs but also to lower lows.

So for fast paced games where you don't want to give the player the possibilty to "invest" into damage variation, the main factor to consider might be @Adams answer, that damage variation helps to flatten out the impact of damage buffs.

Answer 4

The other answers are great, but I wanted to add another perspective to your question.

Dealing the same amount of damage makes a battle more predictable, which could make the game boring. If you have one attack only that deals 100 damage, and your enemy only has one attack that deals 50 damage, and you both have 500 health, your brain can pre-calculate most of the encounter already before it even starts!

For a game to be fun, there needs to be an amount of unpredictability. As you noted critical hits can do that, also dealing variable amounts of damage can also do that.

Having said that, having damage be variable doesn't automatically make a game fun. You need a good balance of, the battle has some unpredictability, but it's also not pure chaos. Different games apply this in different ways, up to you to discover what works for your project!